1. Field of the Invention
The present invention relates to a power-assisted shovel truck equipped with a water-feeding device and a water-draining device. More specifically, the present invention relates to a power-assisted shovel truck capable of feeding water to a bucket at its front and of draining turbid water that hinders visibility during ground excavation.
2. Discussion of the Related Art
Conventional power-assisted shovel trucks are equipped with a rotary bucket device having a mechanism that opens and closes to hold materials. Japanese Laid-Open Nos. 207728/1986 and 240295/1987 disclose such shovel trucks. The holding mechanism of the rotary bucket of these conventional shovel trucks consists of jaws actuated by a hydraulic cylinder. A hydraulic motor drives the rotary bucket so that it fully rotates. A swivel joint near the shaft of the rotary bucket allows the free rotation. Hydraulic pressure is fed through the swivel joint to the hydraulic cylinder that opens and closes the jaws of the holding mechanism. These shovel trucks exhibit high power for performing a variety of functions, for example, digging the earth, holding concrete blocks, and pouring raw concrete.
Although superior to other conventional rotary inclination-adjustable buckets or manually rotated fixed buckets, the rotary buckets as described hereinabove exhibit some limitations. For example, when used to transport raw concrete, the semi-solidified raw concrete adhered to the bucket surfaces tends to increase the weight of the bucket, decrease the effective capacity of the bucket, and hinder the operation and movement of the bucket and its jaws. Similar problems occur during excavation of earth and sand. These buckets require continual cleaning causing work interruption. The bucket is typically cleaned by spraying water onto the bucket while brushing it. This task is laborious and often dangerous.
In addition, ground excavation is often facilitated by first feeding water to the ground in order to make the earth and sand muddy and, therefore, easier to excavate. The water is then sucked and drained from the earth and sand. Conventional devices, however, do not simultaneously excavate and feed the water.
Similarly, the dismantling of, for example, a house or other structure, generates large amounts of dust and dirt unless water is sprayed onto the dismantled structure. Conventional shovel devices do not supply the water, as water must be manually sprayed from a hose.